Rudder

When we uninstall rudder agent, /var/rudder/ncf is not cleaned, leading to bug if you remove a more recent rudder version to an older one, like in #12967:

rpm -i rudder-agent-4.3.x
....
....
# oups, in fact I needed agent 4.1 on that machine:
rpm -e rudder-agent

rpm -i rudder-agent-4.1.y
....
rudder agent run 
....
/var/rudder/cfengine-community/inputs/promises.cf:358:0: error: Undefined bundle _create_current_expected_reports_file with type usebundle
/var/rudder/cfengine-community/inputs/promises.cf:486:0: error: Undefined bundle _clean_old_expected_reports_file with type usebundle
....